MICROWAVE baking bars and cream in medium, microwave-safe bowl uncovered, microwave-safe bowl on MEDIUM-HIGH (70%) power for 1 minute; STIR. The bars may retain some of their shape. If necessary, microwave at additional 10 to 15-second intervals, stirring just until melted. Transfer to small mixer bowl. Beat in powdered sugar, butter and extract until smooth. Stir in food coloring.
SPREAD or pipe icing onto baked and cooled sugar cookies; decorate as desired. Let stand until icing is set.
Makes about 1 1/4 cups.
* Paste food colorings are available where cake decorating supplies are sold.